[tracing] Use locale independent writer for FP values.

src/tracing/traced-value.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/tracing/traced-value.h"
 
 #include "src/base/platform/platform.h"
+#include "src/conversions.h"
 
 namespace v8 {
 namespace tracing {
 
 namespace {
 
 #define DCHECK_CURRENT_CONTAINER_IS(x) DCHECK_EQ(x, nesting_stack_.back())
 #define DCHECK_CONTAINER_STACK_DEPTH_EQ(x) DCHECK_EQ(x, nesting_stack_.size())
 #ifdef DEBUG
 const bool kStackTypeDict = false;
@@ skipping 55 matching lines @@
 
 void TracedValue::SetInteger(const char* name, int value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeDict);
   WriteName(name);
   data_ += std::to_string(value);
 }
 
 void TracedValue::SetDouble(const char* name, double value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeDict);
   WriteName(name);
-  data_ += std::to_string(value);
+  i::EmbeddedVector<char, 100> buffer;
+  data_ += DoubleToCString(value, buffer);
 }
 
 void TracedValue::SetBoolean(const char* name, bool value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeDict);
   WriteName(name);
   data_ += value ? "true" : "false";
 }
 
 void TracedValue::SetString(const char* name, const char* value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeDict);
@@ skipping 19 matching lines @@
 
 void TracedValue::AppendInteger(int value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeArray);
   WriteComma();
   data_ += std::to_string(value);
 }
 
 void TracedValue::AppendDouble(double value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeArray);
   WriteComma();
-  data_ += std::to_string(value);
+  i::EmbeddedVector<char, 100> buffer;
+  data_ += DoubleToCString(value, buffer);
 }
 
 void TracedValue::AppendBoolean(bool value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeArray);
   WriteComma();
   data_ += value ? "true" : "false";
 }
 
 void TracedValue::AppendString(const char* value) {
   DCHECK_CURRENT_CONTAINER_IS(kStackTypeArray);
@@ skipping 47 matching lines @@
 }
 
 void TracedValue::AppendAsTraceFormat(std::string* out) const {
   *out += '{';
   *out += data_;
   *out += '}';
 }
 
 }  // namespace tracing
 }  // namespace v8